Our portable solar window heater design allows you to move the unit to follow the sun for maximum heat gain. These solar window heater are used to supplement an existing home heating system and can save up to 30% to 40% on room heating costs annually. How can a solar window heater help reduce your monthly heating bills? During the fall and winter the sun is low in the sky. South-facing rooms receive the majority of the sun’s direct rays. When a solar window heater is installed, these rooms have more exposure to the sun energy. Our solar window heaters are portable and can be moved to follow the sun.